According to spatial models of elections, citizen perceptions of party policy positions are a key determinant of voting choices. Yet recent scholarship from Europe suggests that voters do not adjust their perceptions to what parties advocate in their campaigns. We argue that leadership changes enable parties, particularly those in opposition, to redefine their ideological image as having a new leader increases the credibility of party policy offerings. Focusing on Western European parties in the 1979-2012 period, we show that having a new leader is a necessary condition for voters to update their perceptions of opposition parties’ left-right placements. For incumbent parties, on the other hand, voters do not use party platforms to form perceptions of party positions, regardless of whether the leader is new or a veteran. Our results have important implications for models of party competition and democratic representation (coauthored with Pablo Fernandez-Vazquez).